CD6 and Linker of Activated T Cells are Potential Interaction Partners for T Cell‐Specific Adaptor Protein

The T cell‐specific adaptor protein ( TSA d) contains several protein interaction domains, and is merging as a modulator of T cell activation. Several interaction partners for the TSA d proline‐rich region and phosphotyrosines have been identified, including the Src and Tec family kinases lymphocyte‐specific protein tyrosine kinase and interleukin 2‐inducible T cell kinase. Via its Src homology 2 ( SH 2) domain, TSA d may thus function as a link between these enzymes and other signalling molecules. However, few binding partners to the TSA d SH 2 domain in T cells are hitherto known. Through the use of in silico ligand prediction, peptide spot arrays, pull‐down and immunoprecipitation experiments, we here report novel interactions between the TSA d SH 2 domain and CD 6 phosphotyrosine ( pT yr) 629 and linker of activated T cells ( LAT ) pT yr 171 , pT yr 191 and pT yr 226 .